Lancet devices are commonly used both in medical facilities and by private individuals to obtain a blood sample from a patient by puncturing the skin of the patient. This is used when only a small amount of blood is required. Diseases, such as diabetes use blood testing at regular intervals to monitor blood sugar levels of the patient. Obtaining a sample of blood usually involves pricking a finger or other suitable body part with a needle. In view of blood-borne diseases, it is important that, after use of the lancet, other persons do not come into contact with the lancet. Thus, an important aspect of a lancet device involves preventing the needle from wounding another person after the skin of the patient has been punctured. The lancet should be shielded, after use of the device, to prevent accidental wounding of another person. Further, the lancet should be disposable to reduce the possibility of disease transmission due to the device being used on other persons. In this respect, the lancet should preferably be a single use device with features to prevent reuse.
U.S. Pat. No. 6,432,120 B1 to Teo discloses a contact activated lancet. 1 The device has a needle holder and a triggler (triggering device) enclosing a lancet structure. The triggler interacts with the needle holder via a triggering element to maintain the spring in a compressed state such that the lancet structure is in a stable standby position which is not easily triggered by accidental bumps on the assembly. The device is assembled with the spring in the compressed state. Lancets such as those disclosed in Teo are pre-armed prior to use on a patient. With pre-armed lancets there is a potential of triggering prior to application on a patient's skin rendering the device not usable.
WO 2005/110227 A1 to Karbowniczek et al discloses a contact activated lancet including a lancet structure with a puncturing element within a housing structure. The device includes a drive spring and a pivotal lever in interference engagement with the lancet structure. An actuator within the housing pivots the lever, to move the lancet structure toward the rearward end of the housing to at least partially compress the drive spring and thereby releasing the lever from interference engagement with the lancet structure allowing the lancet structure to propel forward. Karbowniczek et al discloses a complicated arrangement for retaining and releasing the lancet structure and is difficult to manufacture and assemble.
It would be desirable to provide a robust, disposable lancet device of simple construction which effectively reduces the likelihood of the lance triggering prior to application.